Delimbing and topping blade control linkage

ABSTRACT

A delimbing machine includes an elongate horizontal platform on which full-length trees are placed and along which a bladecarrying carriage is propelled to delimb and then cut the top from a tree stem. The delimbing blades are spring-biased into encirclement of a tree stem and cams mounted on the opposite ends of the platform operate a crank to cause the blades to open to permit a tree to be delimbed to be placed for encirclement by the blades and to permit a delimbed tree to be removed from the blades. The topping blades are also spring-biased toward engagement with the tree stem but are held away from the tree stem by an overcenter linkage which is moved overcenter by a linkage connected to the crank arm for opening the delimbing blades when the delimbing blades reach a predetermined small diameter near the top of the tree stem.

United States Patent Pierrot, III

[451 Sept. 26, 1972 [54] DELIMBING AND TOPPING BLADE CONTROL LINKAGE[72] Inventor: Victor Charles Pierrot, lIl, Du-

buque, Iowa [73] Assignee: Deere & Company, Moline, "1.

[22] Filed: April 16, 1971 [21] Appl. No.: 137,155

[52] US. Cl. ..144/2 Z [51] Int. Cl. ..A0lg 23/02 [58] Field of Search144/2 Z, 3 D, 34 R, 309 AC [56] References Cited UNlTED STATES PATENTS3,618,647 11/1971 Stuart ..144/309 AC 3,620,272 11/1971 Eriksson et a1...144/3 D Primary Examiner-Gerald A. Dost Attorney-H. Vincent l-larsha,Harold M. Knoth, William A. Murray, John M. Nolan and Jimmie R. Oaks[57] ABSTRACT A delimbing machine includes an elongate horizontalplatform on which full-length trees are placed and along which ablade-carrying carriage is propelled to delimb and then cut the top froma tree stem. The delimbing blades are spring-biased into encirclement ofa tree stem and cams mounted on the opposite ends of the platformoperate a crank to cause the blades to open to permit a tree to bedelimbed to be placed for encirclement by the blades and to permit adelimbed tree to be removed from the blades. The topping blades are alsospring-biased toward engagement with the tree stem but are held awayfrom the tree stem by an overcenter linkage which is moved overcenter bya linkage connected to the crank arm for opening the delimbing bladeswhen the delimbing blades reach a predetermined small diameter near thetop of the tree stem.

5 Claims, 3 Drawing Figures rmmtnsirz I912 3.693; 679

SHEET 1 [IF 2 FIG.|

mf i k-* INVENTOR. V. C. PIERROT, Ill

PATENTEBSEPZB I972 SHEET 2 OF 2 INVENTOR. v. c. PIERROT,

DELIMBING AND TOPPING BLADE CONTROL LINKAGE BACKGROUND OF THE INVENTIONThe present invention relates to a mechanism for delimbing and topping atree stem positioned along a platform or track and more particularlyrelates to delimbing and topping blade arrangement having their controlsinterrelated and being mounted on a carriage which is driven along aplatform to first delimb and then to top a tree stem.

It is known to interrelate the controls of delimbing and topping blades,however, the known arrangements lack overall simplicity and reliability.

SUMMARY OF THE INVENTION According to the present invention there isprovided a novel delimbing and topping blade arrangement mounted on andfor movement with a carriage.

An object of the invention is to provide a blade arrangement wherein thedelimbing and topping blades are biased to closed, cutting positions andare movable to open non-cutting positions by common linkage meansoperated by the inertia of the carriage as it moves along the supportingplatform.

A more specific object is to provide a linkage means of the typementioned in the immediately preceding paragraph including an overcentertopping blade linkage for holding the topping blades open and includinga link responsive to the movement of the delimbing blades toward eachother, when following the decreasing diameter of a tree stem duringdelimbing the stem from its bottom to its top, for moving the toppingblade overcenter when the delimbing blades are at a predetermineddiameter of the tree stem.

Still another object is to provide delimbing and topping blade controllinkage means which are simple and reliable.

These and other objects will be apparent from the ensuing descriptionand the appended drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an overall perspective viewof the delimbing machine in which the present invention is embodied.

FIG. 2 is a perspective view of the delimbing and topping bladecarriage, showing the outline of the frame of the carriage in dashedlines and showing parts broken away for clarity.

FIG. 3 is a view similar to FIG. 2 but showing parts removed forexposing the relationship of the cam and the blade control linkage.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring now to the drawings,there is shown a generally T-shaped, self-propelled delimbing machine10. The machine includes a power unit 12 forming the head of the machineand having a horizontal frame 14 to which is fixed one end of anelongate, horizontal delimbing platform 16, forming the leg of themachine. The power unit 12 is supported on a pair of dual-wheelassemblies 17 and 18, located under the opposite ends of the frame 14,and the platform 16 is supported intermediate its ends on a third wheelassembly 20.

A delimbing and topping blade carriage 22 is mounted by means, notshown, for guided movement along the platform 16 between delimbingbeginning and ending positions respectively adjacent the near and farends of the platform 16, relative to the power unit 12. A drive means,not shown, is operatively connected to the carriage 22 for reversiblydriving the latter along the platform 16. The carriage mounting anddrive means form no part of the present invention and for the detailsthereof reference may be had to the copending application Ser. No.120,501 having the same assignee as the present application, and filedby French et al. on Mar. 3, I971.

The carriage 22 includes a main frame 24 overlying and having skirtsstraddling the platform 16. The carriage 22, as viewed moving forwardlyin the direction of the arrow (FIG. 2) by an observer at the power unit12, has a first blade-carrying arm 26 mounted at the left side of theframe 24 for swinging about a fore-and-aft pivot axis defined by a pin28 located adjacent the trailing end of the carriage 22. A secondblade-carrying arm 30 is similarly mounted at the right side of theframe 24 for swinging about a fore-and-aft pivot axis defined by a pin32, the pins 28 and 32 being spaced from each other in the fore-and-aftdirection an amount sufficient for permitting the arms 26 and 28 toswing to overlapped positions. Respectively carried on the outer ends ofthe arms 26 and 30 are a pair of arcuate plate-like blades 34 and 36respectively having opposed concave surfaces 38 and 40 for embracing atree stern and having beveled leading cutting edges 42 and 44 forcutting tree limbs by impact. The blades 34 and 36 are biased towardeach other, for embracing a foreand-aft extending tree stem locatedtherebetween, by a pair of tension springs 46 and 48. The spring 46 hasits opposite ends connected to the right side of the frame 24 and thearm 26 and the spring 48 has its opposite ends connected to the leftside of the frame 24 and the arm 30.

For the purpose of opening the blades 34 and 36 against the bias of thesprings 46 and 48, there is provided linkage means including a pair oftie rods 50 and 52 respectively pivotally connected at one of their endsto the arms 26 and 30. and respectively pivotally connected at the otherof their ends tothe opposite ends of a horizontal output crank arm 54.The crank arm 54 is fixed, midway of its ends, to a vertically extendingcrank pin 56 which is rotatably journaled in a horizontal mounting plate58 forming the bottom of the frame 24. A horizontal input crank arm 60is fixed between its ends, to the crank pin 56 and a pair of rollers 62are respectively mounted for rotation about a pair of vertical pins 64fixed to and extending downwardly from the crank arm 60 at locationsequidistant from the crank pin 56. The pair of rollers 62 arerespectively received in and extend through a pair of kidney-shapedopenings 66 in the mounting plate 58. A pair of vertical surface cams 68and 69 are fixed to the top of the platform 16 respectively at thedelimbing beginning and ending positions, of the carriage 22, adjacentthe near and far ends of the platform 16. The cams 68 and 69 eachinclude first surface portions 70, extending in the direction of travelof the carriage 22, and second surface portions 72 angled to thedirection of travel. The earns 68 and 69 are each fixed to the platform16 such that as the carriage 22 respectively arrives at the cams 68 and69, the rollers 62 first contact the angled surface portions 70, whichcause the input crank arm 60 and, hence, the output crank arm 54 to berotated to an extreme counterclockwise position (FIGS. 2 and 3) whereinthe delimbing blades 34 and 36 are moved apart to their fully openposition. The cam surface portions 72 receive the rollers 62 from theangled cam surface portions 70 and the rollers 62 bear thereagainst toprevent the blades 34 and 36 from closing.

Mounted adjacent the leading end of the carriage 22 are a pair ofvertical topping blade mounting posts 74 and 76. The posts 74 and 76 aretubular and are respectively pivotally received on a pair of rods 78 and80 fixed to and extending vertically upwardly from the mounting plate58. Respectively fixed to the upper ends of the posts 74 and 76 are apair of flat plate-like topping blades 82 and 84 having respectivebeveled cutting edges 86 and 88. The blades 82 and 84 pivot about therods 78 and 80 between an open position wherein they extend parallel toeach other and the direction of travel, as illustrated in F IG. 2, and aclosed topping position wherein they extend perpendicular to thedirection of travel and their cutting edges 86 and 88 meet.

The blades 82 and 84 are biased toward the closed position by means of atension spring 90 having its opposite ends respectively connected toeyes forming the tops of a pair of pins 94 and 96 respectively extendingvertically through a pair of horizontal crank arms 98 and 100 fixed tothe posts 74 and 76. Respectively pivoted to the bottom of the pins 94and 96 are one of the ends of a pair of links 102 and 104 having theirother ends pivotally interconnected by means of a vertical pin 106. Thebottom end of the pin 106 is received in a narrow fore-and-aftextending, centrally located guide slot 108 in the mounting plate 58.The pin 106 is movable between a first position at the leading end ofthe slot 108 wherein it is slightly forwardly of the line joining thecenters of the pins 94 and 96 and wherein the links 102 and 104 areprevented from being folded by the spring 90 and a second position inthe slot 108 rearwardly of the line joining the centers of the pins 94and 96 wherein the links 102 and 104 are caused to be folded by thespring 90 resulting in the blades 82 and 84 being pivotedcounterclockwise and clockwise, respectively. For the purpose ofshifting the pin 106 to the opposite sides of the line intersecting thecenters of the pins 94 and 96, a control rod 110 is slidably received inan eye forming the top of the pin 106 and in an eye forming the top of avertical pin 112 swivelly mounted at the leading end of the input crankarm 60. At the opposite ends of the control rod 110 are abutments forpreventing the rod 1 from being withdrawn from the eyes of the pins 106and 112 and for being respectively engaged by the eye of the pin 112 andfor engaging the eye of the pin 106 to transfer counterclockwise motionof the input crank arm 60 into linear motion for shifting the pin 106 tothe position rearwardly of the center line intersecting the pins 94 and96. An elongate tubular control collar 114 is slidably received on therod 110 between the eyes of the pins 106 and l 12 and its opposite endsare respectively positioned for being engaged by the eye of the pin 112and for engaging the eye of the pin 106 to transfer clockwise motion ofthe input crank arm 60 into linear motion for shifting the pin 106 tothe position forwardly of the centerline intersecting the pins 94 and96.

A boom and grapple assembly 116 is mounted on the frame 14 adjacent theend of the delimbing platform 16 and is hydraulically operable, in theusual manner, for grasping and manipulating tree stems into place of theplatform 16. A retainer-ejector 118 is mounted on the platform 16adjacent the boom and grapple assembly 1 16 and includes a bed 120 whichsupports the stems of trees placed of the platform 16 and against whichsuch stems are clamped by a hydraulically-controlled clamp arm 122.

In operation, the delimbing machine 10 is driven to a position alongsidea tree or a pile of trees, to be delimbed, lying on the ground. Thecarriage drive means (not shown) is appropriately controlled to move thecarriage 22 to its beginning location over the cam 68 at the near end ofthe platform, as shown in FIGS. 2 and 3. In this position of thecarriage 22, the rollers 62 are in engagement with the cam surfaceportion 72 whereby the input crank arm 60 is held in its extremecounterclockwise position wherein the delimbing blades 34 and 36 and thetopping blades 82 and 84 are held open by linkage associated with thecrank arm 60.

The operator then controls the boom and grapple assembly 116 to selectand manipulate a tree stern into position along the top of the platform16 with the top of the tree being at or beyond the far end of theplatform 16 and with the bottom portion of the tree resting on the bed120 and located between the open pairs of delimbing and topping blades34 and 36, and, 82 and 84, respectively. The clamp arm 122 is thenactuated to clamp the tree stem against the bed 120 t0 hold the stemduring the delimbing and topping operations.

At this time, the carriage drive is actuated to quickly advance thecarriage 22 forwardly in the direction of the arrow (FIG. 2), toward thefar end of the platform 16. As the carriage 22 moves from over the cam68, the leading one of the rollers 62 first becomes free of the camsurface portion and the crank arm 62, through the action of thedelimbing blade biasing springs 44 and 46, rotates clockwise aspermitted by the angled cam surface portion 72 or until one of thedelimbing blades 34 and 36 comes into contact with the tree stem.

As the carriage proceeds from the bottom to the top of the tree stem,the springs 44 and 46 tend to keep the concave surfaces 38 and 40 of thedelimbing blades 34 and 36 in embracing relationship with the tree stemso as to dispose the sharpened leading edges 42 and 44 as closely aspossible to the tree stem so as to cut the limbs off at their juncturewith the tree stem.

Since tree stems are naturally tapered from their bases to their tops,the blades 34 and 36 will move closer together and the input crank arm60 will continue to be rotated clockwise by the action of the springs 44and 46, as the carriage 22 advances toward the far end of the platformand thus toward the top of the tree stem. As the input crank arm 60rotates clockwise, the eye at the end of the pin 112 slides rearwardlyon the control rod until it engages the abutment on the trailing end ofthe rod 110 and then it causes the rod 110 to slide rearwardly until theabutment at the leading end of the rod 110 engages the eye of the pin106. At this point, further clockwise rotation of the input crank arm 60results in the pin 106 being moved rearwardly in the guide slot 108.When the delimbing blades 34 and 36 engage a predetermined diameterportion of the tree stem, the control linkage is designed such that thepin 106 is moved rearwardly of the centerline joining the pins 94 and 96and the action of the tension spring 90 collapses the links 102 and 104and rotates the topping blade-carrying posts 74 and 78 to swing thetopping blades 82 and 84 to the closed position to engage their cuttingedges 86 and 88 with the tree stem. The movement of the carriage 22 thencauses the angled blades to bite into the tree stem and continuerotating together to remove the top of the stem.

Meanwhile, the carriage drive means has been operated to cause thecarriage 22 to come to a smooth stop at the far end of the platform 16and as the carriage 22 is stopping its momentum carries it to a positionover the cam 69, which cam is engaged by the rollers 62 and causes theinput crank arm 60 to be rotated to the extreme counterclockwiseposition. During the counterclockwise rotation of the crank arm 60, theeye of the pin 112 engages the control collar 114 and slides the collarforwardly on the rod 110 into engagement with the eye of the pin 106 andmoves the latter to the leading end of the slot 108. As the pin 106moves forwardly in the slot 108, it causes the links 102 and 104 to beunfolded resulting in the support posts 74 and 78 being rotated todispose the topping blades 82 and 84 in the opened position, whereinthey extend parallel to each other. It is to be noted that thecounterclockwise rotation of the input crank arm 60 has at the sametime, through means of the output crank arm 54 and the tie rods 50 and52, opened the delimbing blades 34 and 36. The delimbed tree stem maythen be lifted from between the delimbing blades 34 and 36.

The carriage drive means is then reversed to return the carriage to itsbeginning location. As the carriage 22 leaves the cam 69, the delimbingand topping blades will again close, as described above, and as thecarriage 22 approaches the beginning position over the cam 68 at thenear end of the platform 16, the delimbing and topping blades will againbe opened in the manner described above.

What is claimed is:

1. A delimbing and topping apparatus comprising: a blade carriageadapted for movement along a guide track positionable lengthwise of atree stem, said carriage including a frame; a pair of delimbing bladesand a pair of topping blades respectively pivotally mounted at oppositesides of said frame for swinging movement toward and away from eachother and crosswise to the intended direction of movement of saidcarriage; biasing means urging each of said pairs of delimbing andtopping blades toward each other respectively to delimbing and toppingpositions; control linkage means connected between said frame and saiddelimbing and topping blades for moving the respective pairs of thelatter away from each other against the action of the biasing means torespective inactive positions for receiving a tree stem in or ejecting atree stem from a position extending between the pairs of blades in thedirection of intended travel of the carriage; said control linkage meansincluding separate delimbing and Ehiil'lg a ii e irfilli lo v'iii fieivfi rlis lfifiii fiolld positions corresponding to extreme apart andtogether positions of said pair of delimbing blades and an over centerlinkage movable between first and second overcenter positions atopposite sides of an on-center position respectively for preventing saidbiasing means from and for permitting said biasing means to move saidpair of topping blades from the inactive to the topping position; andlost-motion link means interconnecting said element and said overcenterlinkage for moving said overcenter linkage to said first overcenterposition when said element is moved to said first position and formoving said overcenter linkage to said second overcenter position whensaid element is at a predetermined position between said first andsecond positions.

2. The invention defined in claim 1 wherein said delimbing blade controllinkage means includes a crank pin rotatably mounted in said frame, andsaid element being a crank arm secured to said crank pin.

3. The invention defined in claim 2 wherein said overcenter linkageincludes a pair of links pivotally interconnected at one of their endsby a pivot pin and said lost-motion linkage having one end connected tosaid pivot pin.

4. The invention defined in claim 3 wherein said pivot pin has an eyeformed integral therewith; a second pivot pin having an eye integraltherewith and being swivelly mounted in said crank arm for movementabout an axis parallel to the axis of the crank pin; and saidlost-motion linkage means including a rod extending through said eyes ofsaid pivot pins and having abutments at its opposite ends and a collarslidably received on said rod and having its opposite ends located onthe opposite sides of said eyes from said abutments; and the rod andcollar being dimensioned such that when said crank arm is at said firstposition, the opposite ends of said collar will be in contact with saideyes and when said crank arm is at said predetermined position saidabutments will be in contact with said eyes.

5. The invention defined in claim 3 wherein said overcenter linkageextends generally vertically to the pivotal axes of said topping blades;said frame including a plate positioned adjacent to and extendingnormally to said pivot pin; a guide slot being located in said plate andextending vertically to a line determining the oncenter position of saidovercenter linkage and said pivot pin being received for guided movementin said slot.

1. A delimbing and topping apparatus comprising: a blade carriageadapted for movement along a guide track positionable lengthwise of atree stem, said carriage including a frame; a pair of delimbing bladesand a pair of topping blades respectively pivotally mounted at oppositesides of said frame for swinging movement toward and away from eachother and crosswise to the intended direction of movement of saidcarriage; biasing means urging each of said pairs of delimbing andtopping blades toward each other respectively to delimbing and toppingpositions; control linkage means connected between said frame and saiddelimbing and topping blades for moving the respective pairs of thelatter away from each other against the action of the biasing means torespective inactive positions for receiving a tree stem in or ejecting atree stem from a position extending between the pairs of blades in thedirection of intended travel of the carriage; said control linkage meansincluding separate delimbing and topping blade-control linkage meansrespectively including an element movable between first and secondpositions corresponding to extreme apart and together positions of saidpair of delimbing blades and an overcenter linkage movable between firstand second overcenter positions at opposite sides of an on-centerposition respectively for preventing said biasing means from and forpermitting said biasing means to move said pair of topping blades fromthe inactive to the topping position; and lost-motion link meansinterconnecting said element and said overcenter linkage for moving saidovercenter linkage to said first overcenter position when said elementis moved to said first position and for moving said overcenter linkageto said second overcenter position when said element is at apredetermined position between said first and second positions.
 2. Theinvention defined in claim 1 wherein said delimbing blade controllinkage means includes a crank pin rotatably mounted in said frame, andsaid element being a crank arm secured to said crank pin.
 3. Theinvention defined in claim 2 wherein said overcenter linkage includes apair of links pivotally interconnected at one of their ends by a pivotpin and said lost-motion linkage having one end connected to said pivotpin.
 4. The invention defined in claim 3 wherein said pivot pin has aneye formed integral therewith; a second pivot pin having an eye integraltherewith and being swivelly mounted in said crank arm for movementabout an axis parallel to the axis of the crank pin; and saidlost-motion linkage means including a rod extending through said eyes ofsaid pivot pins and having abutments at its opposite ends and a collarslidably received on said rod and having its opposite ends located onthe opposite sides of said eyes from said abutments; and the rod andcollar being dimensioned such that when said crank arm is at said firstposition, the opposite ends of said collar will be in contact with saideyes and when said crank arm is at said predetermined position saidabutments will be in contact with said eyes.
 5. The invention defined inclaim 3 wherein said overcenter linkage extends generally vertically tothe pivotal axes of said topping blades; said frame including a platepositioned adjacent to and extending normally to said pivot pin; a guideslot being located in said plate and extending vertically to a linedetermining the on-center position of said overcenter linkage and saidpivot pin being received for guided movement in said slot.